Thanks to all for these great fuse comments and experiences. I have recently ordered a few Furutech fuses for my amps (Spectron monoblocks...could use a little Furutech smoothness), one of my pre's (Wyred STP SE) and one (oops) for my Weiss DAC2. I say "oops" cuz the 500mA fuse arrived a couple days ago (the rest haven't) and lo and behold the damn DAC takes two (2) of them. It's one of those doors next to the IEC inlet. Has two stacked fuses, one neutral, one phase. So I replaced the top one (dunno which is which). Do you guys expect weird results with one leg Furutech rhodium (I have the other fuse on order now), and one leg a standard stock fuse? So far, after 24 hrs, upper mids and lower treble actually sound a little brittle...but no where near broken in.
Thx
Ted

Thanks. I will go one variable at a time and let it break in another 48 hrs or so; then I'll reverse it. I'll report back...but again, I only have it on one leg of the AC so it may be moot until I get the other one installed and settled in. Thanks again,
Ted

Big Poppa,
That was it!! I reversed it after letting it settle in a bit more and voila, it's much clearer and more dynamic. It had sounded like I had all of a sudden gotten congested on complex passages, as if my 800 watt per channel Magtech amp was straining! Not any more. Thanks. Can't wait for the other fuse for the other leg of this ac.

Fuse direction matters. The difference is usually discernable without trying to listen too hard.

When inserted the wrong way, the sound will usually be a bit flatter and softer. Imaging not as good. It can still sound OK, just not "right".

On fuses with directional arrows - you should still experiment. Unless you are a circuit designer or tech, you may not know the true direction of flow in the circuit. Some boards have been known to be marked incorrectly.

In testing marked fuses here, it's been determined that the fuse manufacturers are marking them correctly for directionality.

Sorry, I am not knocking them. I don't know what i said to make you think that.

I am confused though. I am struggling to understand how a rhodium plated and cryo'd 1/4" length of copper wire can have different properties if you turn it around.

The fuse is only about 1/4 in long, yes?. If you can argue that a 12" run of power cable makes subtle differences to the sound, then what sort of differences can a 1/4" long piece of wire at the end of it make to your system? And you can hear differences by turning this 1/4" piece of wire around the other way.

Have you tried taking the fuse out and replacing it back the same way around? I am thinking just the act of taking the fuse out could be removing a layer of oxidation at the contacts. So the change you are hearing might not be for the reason you think.